Window shutter



Dec. 19, 1933. M. DEMEULENAERE 1,940,583

' WINDOW SHUTTER Filed May 29, 1930 3 Wu em to o Mrae] .Uemeu/snaere Patented Dec. 19, 1933 UNITED} STATES PATENT OFFICE Application e in Belgium 2 Claims.

orby using a varying balance weight'with a constant length of level.

The object of my present invention is to provide an improved balancing device of the last mentioned type.

Broadly stated the varying balance weight of my invention is constructed in such a way that it may be formed of parts which are always similar for any size, width, thickness, weight, etc. of the window shutter, andadapted to be manufactured .by punching or inany other similar way, in the shape of blades orthe like. A number of such blades are assembled to form a section of the balance weight and these sections are pivotally connected 'to eachother in zig-zag form to constitute the entire balance weight.

In order that my invention may be easily understood, I have illustrated the same by way of example in the accompanying drawing, in which:

Fig. 1 is a front elevation of the window shut ter in its closed position.

Fig. 2 is a corresponding side elevation, and Fig. 3 is a section on line 3-3 of Fig. 2. Referring now moreparticularly to the drawing, V designates the shutter adapted to be wound around a roller A from the diameter DA to the diameter DA, DM being the average diameter thereof. Made integral with the roller A is a smaller roller A around which a belt or cable C may be wound up from the diameter dc to the diameter da, dm being the average diameter. After the shutter V has been lowered, it will act on the diameter DA and thebelt or cable 0 which is now wound around the roller A will act on the diameter (211', that is the maximum diameter. Attached to said belt or cable C is a series of balance weights La, the total weight of which exactly balances the weight of the shutter. P and p designating the total weight of the shutter and balance weight respectively. It will be obvious that P DA=p da', the frictions on the guide rollers F and f for the shutter V and belt C respectively being not taken into consideration.

In the case in which the balance weight is at- May 29, 1930, Serial No. 457,416, and,

July 13,1929

taohed to a cable I may also maintain a constant winding diameter equal to dm. The shutter V of a weight P being wound upon a diameter D, I will have P D=p.dm.

In accordance with the raising of the shutter V, the balance weights or section La will be made inoperative, the lowermost sections La resting on the ground and the following sections being successively placed upon said lowermost section and upon each other. e

After the shutter has been completely raised, all thesections of the balance weight will rest on each other. The blades La are pivotally con-'- neoted together by means of pins a journaled in thin bushings 11 secured to plates is. After all the balance weight sections have been raised, they will have the appearance of an accordeon. The

shutter will be opened according to the lowering of the balance weight sections. The number. of sections may be varied as desired and the number of blades in each section may be determined according to the graduationof the weight of the shutter. I

This result may be obtained by using extended pins a and securing the thin blades La side by side. In this way, I will obtain an increase of weight with the same parts constituting the balancing device for shutters of any size, width, thickness and weight.

I claim: y e

1. In a shutter of the kind described, the combination with a rotatable roller and a shutter adapted to be wound around said roller, of a reduced roller made integral with the first named roller, a belt adapted to be wound around said reduced roller, a balance weight attached to said belt, said balance weight being'formed of a number of sections, alternately attached to each other at opposite ends by means-of pivotal connections, whereby said sections will be adapted to rest on the ground and oneach other according to the raising of the shutter, substantially as set forth.

2. In a shutter of the kind described, the combination with a rotatable roller and a shutter adapted to be wound around said roller, of a reduced roller made integral with the first named roller, a belt adapted to be wound around said reduced roller, a balance weight attached to said 

